<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS学习</title>
    <style>
        /* div {
            color: red;
        } */
        /* a {
            color: blueviolet;
        } */
        /* .div1 {
            color: red;
        } */

        /* #one {
            color: green;
        } */
        /* * {
            color: brown;
        } */
        /* li {
            color: red;
        } */

        /* .c1 {
            color: red;
        } */
        /* ul li {
            color: green;
        }
        ol li {
            color: red;
        }
        ol li a {
            color: purple;
        } */

        /* ol a {
            color: green;
        } */
         /* .c1 a {
            color: green;
         } */

         /* a, span{
            color: rgb(251, 100, 12);
            font-size: 2em;
        
         } */

         #one {
            /* border-color: black;
            border-style: solid;
            border-width: 10px; */

            /* border: solid  red 5px; */
            /* border-width: 10px 5px 2px 1px; */

            /* border-top-width: 10px;
            border-right-width: 5px;
            border-bottom-width: 2px;
            border-left-width: 1px; */
            /* width: 200px;
            height: 100px; */
         }
         .div1 {
            width: 200px;
            height: 100px;
            border: solid  red 5px;
         }
         span {
            display: block;
         }

    </style>
</head>
<body>
    
    <div class="div1" id="one">我是一个div111</div>
    <div>我是一个div222</div>
    <div><a href="#">我是一个div333</a></div>
    <div><span class="div1">我是一个div444</span></div>
    <ul>
        <li>aaa</li>
        <li>bbb</li>
        <li>ccc</li>
    </ul>
    <ol>
        <li class="c1">ddd</li>
        <li class="c1">eee</li>
        <li class="c1"><a href="#" >fff</a></li>
    </ol>
</body>
</html>